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Best 0-320 upgrade package

S

stifler

Active Member
Guys
Just looking for a little advice here, I've got a timed out 0-320 E2A to rebuild & upgrade for my #6 rebuild project and I'm looking to get (within budget ) the best possible package. What is the best upgrade kit can I buy ( I hear you can get 175hp) from a 0320? What is the best propeller I should get to match this new spec? I'm not just looking for top speed (but that would be nice) but a package that best suits the aircraft and most flying situations.
Obviously I need to keep an eye on the costs and if you have got an approx cost that would be great.
Thanks
Steve
 
Go to 160 HP

If you rebuild with new cylinders then an upgrade to 160HP with higher compression pistons would almost be a no-cost option.

The two piece front bearing can easily be changed to a later single piece one when the case is overhauled and you will be almost to an O-320-D model.

The one con is you will need 100LL (or it's future replacement) rather than lower octane auto fuel.

But, from the Petersen STC page..

The 160 hp 0-320 auto fuel STC requires 91 AKI minimum
 
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I'm no expert by any means... but it seems that you'd be better off selling the times out 320 and getting a timed out 360 and having some fun with it. I know that times are a-changin, and they are doing very fun things with engines these days, but there is no replacement for displacement. It would probably be a wash in price or close to it.

By the time you maxed out HP on an 0320, you might be slightly above what a stock 360 would merit you. Then, if you still wanted to do the upgrades, you be HP ahead for nearly the same money.

Upgrades cost money. The same money to upgrade an 320 vs 360.
Overhaul cost are equal
Sell the 320 for 360... nearly equal.

Just my $.02 with. It's worth exactly what you paid for it. 👍
 
I'm no expert but.........

Hi

The E2a should be a single piece front bearing. There is an STC on upgrading to 160 GP. 8.5/1 pistons, nitrided cylinders. While you are at it fit heAvy wall gudgeon pins (writer pins for US)

EI gives more power and better fuel consumption and the possibility of running lean of peak. To get the best out of this engine go for a CS prop. The give good performance with FP too.

Am 0-360 will add weight. I am considering an -340 for my 4 same weight as an 0-320 but 180 hp.

You can push up the compression ratio for more Hp but as has been said will limit your fuel choice to 100ll
 
Pmag right side, 9.5-1 compression pistons and port/polish the cyclinders will get 175+hp. Add a catto three blade prop made for your engine and airframe combo and fly the snot out of it. I have a -b2c that is already 160hp and will be adding pistons and pmag soon. This will turn my super cruise catto three blade prop into a climb/cruise prop. I can currently only turn 2160rpm static, 2620rpm WOT at 1000ft agl and 1500 fpm climb solo with 30 gals of fuel at 75 degs. This gives me 190mph in an rv6. 2500rpm is 170mph normal cruise.

I also trimmed my exhaust pipes to not hang down below the cowling and made a cooling air exit fairing like the rv8's firewall radius. In back to back speed runs 2 hrs apart, i picked up 4 mph speed at WOT and 1000ft agl.

Pmag $1300
Pistons with new rings $800
Port/polish $1000
 
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You could get it stroked to an IO-340 + FI + Pmags and you are hitting close to 190hp for the weight of an io-320 instead of an o-360, maybe a 10lb saving for similar configurations?
 
WAM120RV said:
Hi

EI gives more power and better fuel consumption and the possibility of running lean of peak. To get the best out of this engine go for a CS prop. The give good performance with FP too.

Hi Steve

Would this mean I would have to change my crankshaft to change to a CS prop??
Click to expand...
 
gfb said:
You could get it stroked to an IO-340 + FI + Pmags and you are hitting close to 190hp for the weight of an io-320 instead of an o-360, maybe a 10lb saving for similar configurations?
Click to expand...

This is my recommendation. it will mean you will need a new prop, if you are running a fixed pitch. The following is from the Twin Navion website and is for the carbureted version.

http://www.twinnavion.com/o340.htm said:
Operating the O-340:
The O-340 behaves no differently than either the O-320, or the O-360; it's still a carbureted four-cylinder, horizontally opposed engine. Unlike some earlier piston engines, it produces full power, 170hp continuously.
Maintenance:
As it's been mentioned before, the O-340 is no different than either of its O-320 or O-360 brothers. The same goes for the care and maintenance. The difference is in some of the unique parts used.
Some of the parts/modifications unique to the O-340 are:
Larger center and rear crankshaft bearings.
Larger bearing chambers in the crankcase, making it a -30 case.
A unique crankshaft.
Shortened connecting rods.
Shorter connecting rod bolts (can be cut down from longer bolts).
Unique air intake pipes, caused by the step down between cylinder and crankcase.
Longer push-rods and push-rod tubes.
Carburetor limited to prevent full throttle.
Click to expand...
 
stifler said:
Would this mean I would have to change my crankshaft to change to a CS prop??
Click to expand...

If you don't currently have a hollow crank, it would need to change for a CS prop. There might be other changes too if you engine was not originally set up for CS.
 
gfb said:
If you don't currently have a hollow crank, it would need to change for a CS prop. There might be other changes too if you engine was not originally set up for CS.
Click to expand...

This might be a possibility as I need to get the crank inspected as it had a stationary prop strike from a hard landing. I will se what the inspector says.
 
stifler said:
This might be a possibility as I need to get the crank inspected as it had a stationary prop strike from a hard landing. I will se what the inspector says.
Click to expand...

Verify your case will work with a CS prop. It is not all about the crank.
 
exhaust trimming & cooling air exit ? can you give me more info on this

titanhank said:
Pmag right side, 9.5-1 compression pistons and port/polish the cyclinders will get 175+hp. Add a catto three blade prop made for your engine and airframe combo and fly the snot out of it. I have a -b2c that is already 160hp and will be adding pistons and pmag soon. This will turn my super cruise catto three blade prop into a climb/cruise prop. I can currently only turn 2160rpm static, 2620rpm WOT at 1000ft agl and 1500 fpm climb solo with 30 gals of fuel at 75 degs. This gives me 190mph in an rv6. 2500rpm is 170mph normal cruise.

I also trimmed my exhaust pipes to not hang down below the cowling and made a cooling air exit fairing like the rv8's firewall radius. In back to back speed runs 2 hrs apart, i picked up 4 mph speed at WOT and 1000ft agl.

Pmag $1300
Pistons with new rings $800
Port/polish $1000
Click to expand...
can you explain this to me more on the exhaust and cooling vent ?
 
If you run too high a compression ratio, you might not be able to run new fuels if they finally replace 100LL. There are lots of "ifs" to be resolved, though...

And remember that speed goes as the cube root of power. In other words, 9% more power gets you 3% more speed.

On my RV-9A, I really wish it had a constant speed prop -- better takeoff, climb, and shorter landing roll with more prop drag. Top speed would be unchanged.
 
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